Cooled laminated conductor ribbon with spacers

ABSTRACT

A laminated electric conductor ribbon which has, at its two opposite ends, electric coupling terminals, is disposed within a hose that extends between the two terminals. The latter are provided with flow passages to permit the circulation of a liquid coolant through the hose.

United States Patent [1 1 [111 3,796,819

Wagner et al. 1 Mar. 12, 1974 COOLED LAMINATED CONDUCTOR RIBBON WITH SPACERS [56] References Cited [75] Inventors: Alfred Wagner; Vladimir Bruckler, UNITED STATES PATENTS both of Essen Germany 2,440,668 4/1948 Tarbox 174/15 c x [73] Assigneez Fried Krupp cesenschaft i 2,943,133 6/1960 Leathers 174/15 C beschrankter Haftung, Essen, 3,043,901 7/1962 Gerwmg et al 174/15 C Germany Primary Examiner-Bernard A. Gilheany [22] 1973 Assistant ExaminerA. T. Grimley [21 A L M0,; 338,627 Attorney, Agent, or Firm-Spencer & Kaye [30] Foreign Application Priority Data ABSTRACT 1972 Germany 22122l4 A laminated electric conductor ribbon which has, at its two opposite ends, electric coupling terminals, is 174/15 /1l F, disposed within a hose that extends between the two 219/209 terminals. The latter are provided with flow passages [51] Int. Cl. H01b to permit the circulation of a coolant through [58] Field of Search.... 174/15 C, 19, 117 R, 117 F, h h

174/117 FF, 28, 29, 47, 129, DIG. 6;

219/209, 546, 549 8 Claims, 3 Drawing Figures 7 III III COOLED LAMINATED CONDUCTOR RIBBON WITH SPACERS BACKGROUND OF THE INVENTION This invention relates to a flexible conductor, such as an electrically conducting ribbon which is formed of laminae and which is provided with a terminal at both of its ends. The ribbon is used in particular for carrying electric current to electrically heated metallurgical furnaces.

It is known to use laminated conductor ribbons for establishing an electrical connection between transformers, generators or high current tubes on the one hand and bus bars, contact faces, contact shoes or the like, on the other hand. These current carrying flexible ribbons are generally formed of several layers of thin sheet metal strips which allow the ribbon terminals to move with respect to one another in one place. In order to accomplish a sufficient flexibility of the ribbons, the individual laminae must be very thin.

The afore-outlined, freely exposed conductor ribbons have several disadvantages. The individual laminae oxidize very rapidly at their surface down to a depth of approximately 0.1 mm, whereby approximately 20 25 percent of the entire cross-sectional area is lost as an electric conductor. The thus increased electric resistance (specific load) causes an increase of the heat loss which, in turn, gives rise to a further increase of the specific electric resistance. An additional reduction in the cross section is caused by the abrasive effect of dust particles between the laminae; this may easily lead to the destruction of the laminae. Although these disadvantages could be reduced by making the laminae thicker, such solution is not feasible because of flexiblity considerations.

Despite the above-noted flexibility considerations, a substantial over-dimensioning of the total cross section of the current carrying ribbon is often necessary. The thus resulting relatively large geometrical dimensions increase, in a substantial degree the reactance of largecurrent conductors which, however, should be of reactance-free structure in case of metallurgical electrical furnaces. For the same reason there appears a nonuniform current distribution which leads to further temperature and loss increases.

SUMMARY OF THE INVENTION It is an object of the invention to provide an improved laminated conductor ribbon from which the aforediscussed disadvantages are eliminated.

This object and others to become apparent as the specification progresses are accomplished by the invention according to which, briefly stated, the conductor ribbon is disposed within a flexible, fluid-tight hose extending between the two terminals attached to the ribbon ends and carrying a coolant liquid. The latter is in circulation through the hose by virtue of flow passages provided in the terminals.

With this arrangement, in addition to eliminating the disadvantages of non-cooled ribbons, it is achieved that the current-carrying parts which are connected to one another by the conductor ribbon and in general are liquid cooled, do not have to be provided with a separate coolant circuit.

In a further embodiment of the invention, between the ribbon and the flexible hose there are provided spacers distributed over the length of the ribbon and having openings to allow the passage of the coolant. In this manner the cross section for the throughgoing coolant is maintained at a substantially constant value and, at the same time, a contact between the flexible hose and the laminae is prevented.

A uniform coolant flow and thus a uniform cooling is enhanced by a further feature of the invention according to which thecross section of the openings in the spacers corresponds approximately to that of the flow passages provided in the terminals.

The invention makes possible to economize to a substantial extent with the structural materials, since, for the same current intensity, a substantial reduction in the cross section of the liquid-cooled current carrying ribbons may be effected. Since the terminals at the ends of the ribbon also may have smaller dimensions, the costs are further significantly reduced.

BRIEF DESCRIPTION OF 'THE DRAWINGS FIG. 1 is a longitudinal, partially sectional view of a preferred embodiment of the invention.

FIG. 2 is a sectional view taken along lines IIII of FIG. 1.

FIG. 3 is a sectional view taken along lines IIIIII of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to FIG. 1, the current-carrying ribbon 1 is formed of two lamina stacks 2 which at each end are firmly secured to two opposite terminals 3 by means of plate rivetings 4, 5. The ribbon 1 is surrounded by a flexible hose 6 which, by means of tube clamps 7 is tightened in a fluid-tight manner to the terminals 3.

Referring now to FIG. 2, at opposite sides of the lamina stacks 2 there are inserted, between the stack edges and the inner wall face of the hose 6, semicircular spacers 9 arranged in opposed pairs and forming mirror images of one another. Each spacer 9 is provided with spaced cutouts 8 to accommodate the thickness of the two lamina stacks 2. In this manner the distance between each stack 2 and the hose 6 is fixed. The spacers 9 are held in space by the inner wall face of the hose 6 and by flexible spacer sleeves 10 disposed between longitudinally adjacent spacers 9. A cable 12 is passed through the spacer sleeves l0 and through bores 11 provided in the semicircular spacers 9 and is attached to the terminals 3.

The terminals 3 which are made of an electrically conducting material, have anoutwardly open central bore 13 which is in communication with three flow passages 14, as best seen in FIG. 1. The passages 14 are so dimensioned that the free flow passage section formed by the intermediate spaces 15 between two opposed spacers 9 (FIG. 2) for the coolant will not be substantially decreased. The external thread 16 provided on the terminals 3 serves for securing the latter by means of a sleeve nut (not shown) to the components that carry the electric current and the coolant in either direction.

The spacers 9, the spacer sleeves 10 and the cables 12 are made of electrically non-conducting materials which, in addition, are insensitive to the effect of the coolant. Preferably, their surface should have a Shore hardness of at least 80. Primary consideration may be given to heat-resistant synthetic materials. The flexible hose 6 may be made of rubber which has to be devoid of metallic inserts.

The structural design of the embodiment described above makes possible a rapid installation and removal of the current-carrying ribbon as well as a simple and rapid replacement of the spacers 9, the spacer sleeves 10, the cables 12 and the flexible hose 6. It is to be understood that by simple structural alterations of the preferred embodiment it is feasible to provide a single lamina stack or, conversely, three or more lamina stacks instead of the two lamina stacks described.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

We claim:

1. In a conductor assembly having a current-carrying laminated ribbon formed of at least one lamina stack and having two opposite ends each provided with a terminal, the improvement comprising:

a. a flexible hose extending between said terminals and spacedly surrounding said ribbon disposed therein;

b. means defining flow passages in said terminals, said flow passages communicating with the space within said hose for permitting a liquid coolant to flow therethrough; and

c. a plurality of spacers distributed along the length dimension of said ribbon, each spacer being provided with a cutout receiving an edge portion of said lamina stack to maintain the distance between said lamina stack and said hose.

2. In a conductor assembly having a current-carrying laminated ribbon with two opposite ends each provided 4 with a terminal, the improvement comprising:

a. a flexible hose extending between said terminals and spacedly surrounding said ribbon disposed therein;

b. means defining flow passages in said terminals, said flow passages communicating with the space within said hose for permitting a liquid coolant to flow therethrough; and

c. a plurality of spacers distributed along the length dimension of said ribbon, each spacer being disposed between and being in engagement with said ribbon and an inner wall face of said hose, each spacer occupying only one part of the hose cross section for providing an opening for the coolant flow.

3. An improvement as defined in claim 2, wherein the cross section of the flow passages in either terminal and the cross section of any opening bounded by one of said spacers are approximately of the same magnitude.

4. An improvement as defined in claim 2, further comprising means defining a hole in each said spacer and a cable extending longitudinally within said hose and passing through said holes.

5. An improvement as defined in claim 4, further comprising spacer sleeves inserted on said cables and disposed between two longitudinally adjacent spacers.

6. An improvement as defined in claim 4, wherein said cable is attached to said terminals.

7. An improvement as defined in claim 2, wherein said spacers are arranged in opposed pairs; the two spacers of a pair are mirror images of one another.

8. An improvement as defined in claim 7, wherein said spacers have a semicircular edge portion in contact with said inner wall face of said hose. 

1. In a conductor assembly having a current-carrying laminated ribbon formed of at least one lamina stack and having two opposite ends each provided with a terminal, the improvement comprising: a. a flexible hose extending between said terminals and spacedly surrounding said ribbon disposed therein; b. means defining flow passages in said terminals, said flow passages communicating with the space within said hose for permitting a liquid coolant to flow therethrough; and c. a plurality of spacers distributed along the length dimension of said ribbon, each spacer being provided with a cutout receiving an edge portion of said lamina stack to maintain the distance between said lamina stack and said hose.
 2. In a conductor assembly having a current-carrying laminated ribbon with two opposite ends each provided with a terminal, the improvement comprising: a. a flexible hose extending between said terminals and spacedly surrounding said ribbon disposed therein; b. means defining flow passages in said terminals, said flow passages communicating with the space within said hose for permitting a liquid coolant to flow therethrough; and c. a plurality of spacers distributed along the length dimension of said ribbon, each spacer being disposed between and being in engagement with said ribbon and an inner wall face of said hose, each spacer occupying only one part of the hose cross section for providing an opening for the coolant flow.
 3. An improvement as defined in claim 2, wherein the cross section of the flow passages in either terminal and the cross section of any opening bounded by one of said spacers are approximately of the same magnitude.
 4. An improvement as defined in claim 2, further comprising means defining a hole in each said spacer and a cable extending longitudinally within said hose and passing through said holes.
 5. An improvement as defined in claim 4, further comprising spacer sleeves inserted on said cables and disposed between two longitudinally adjacent spacers.
 6. An improvement as defined in claim 4, wherein said cable is attached to said terminals.
 7. An improvement as defined in claim 2, wherein said spacers are arranged in opposed pairs; the two spacers of a pair are mirror images of one another.
 8. An improvement as defined in claim 7, wherein said spacers have a semicircular edge portion in contact with said inner wall face of said hose. 